Device for introducing air into steam-boiler furnaces.



No. 627,688. Patented lune 27; I899.

H. HABLAN.

DEVICE FUR lNTBODUClNG AIR INTU STEAM B0|LER FURNACES. I (Application flied May 2, 1899.) (No Model.)

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I I UNITED I STATES PATENT I OrFIcE.

HOWARD HARLAN, or RICHMOND, vrnernrn.

DEVICE FOR INTRODUCING AIR INTO STEAM-BOILER FURNACES.

e .SPECIFIGATIONjor'ming part of Letters Patent No. 627,688, dated June 27, 1899.

Application filed May 2, I899- Serial No. 715,361. (No model.)

T0 at whom it may concern:

Be it known that I, HOWARD HARLAN, a citizen of the United States, residing at Richmond, in the county of Henrico and State of Virginia, have invented certain new and useful Improvements in Devices for Introducing Air into Steam-Boiler Furnaces; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to. the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to certain new and useful improvements in devices for introducing air into steam-boiler furnaces to produce a more complete combustion of the gases in the furnace, and more specifically the invention resides in the provision of a furnace having preferably a double-arch ceiling supported at its center on a fireproof column, said arch extending from the bridge-wall over portions of the grate and having recesses or apertures in the bridge-wall, through which air is conveyed from the outside to the spaces above the grate and underneath the arches, suitable provision being made for regulating the supply of air which enters through ducts leading from the rear wall of the furnace through into the furnace proper, said ducts being preferably below the upper or highest portion of the arch or bridge-wall for the purpose of protecting the same from excessive heat.

To these ends and to such others as the invention may appertain, the same consists, further, in the novel construction, combination, and adaptation of parts, as will be hereinafter more fully described and then specifically defined in the appended claim.

My invention is clearly illustrated in the accompanying drawings, which, with the letters of reference marked thereon, form a part of this application, and in which similar letters of reference indicate like parts throughout both views, in which 1 Figure 1 is a vertical sectional view through the furnace on line 1 1 of Fig. 2. Fig. 2 is a verticalcross sectional view.

Reference now being had to the details of the drawings by letter,'A A designate the arches over the grate-sections B, and the inner ends of said arches are supported on the fireproof column 0. These arches extend, preferably,a considerable distance over the grates, as it is found from practice that the best results are obtained by a construction of this kind, the air entering through the bridge-wall from the outside through the back or side wall. In the recessed portion D of the bridge-wall D the pipes E enter, there being preferably two under each arch, as shown, and these pipes open near the-upper end of the bridgewall. Leading from the recesses D in the bridge-wall are apertures d, opening through from the saidrecesses into the space above the bridge-wall. The outer end of each of said lines or pipes E is provided with a slidevalve G, which works in the vertical slots in the casing H, secured to the end of the flue, whereby as the said slide is raised or lowered the supply of air may be regulated. These fiues E are preferably horizontally disposed in the furnace and are made of any suitable material to protect them from the excessive heat which passes over the bridge-wall in its course to and through the lines of the boiler above.

From the foregoing it will be noted that by the construction of a'double curve or dip bridge-wall I am enabled to utilize the air which is introduced for the purpose of completing the combustion to the best advantage, as has been proven by experiments in the art.

I am aware that it is'comm'on in the art to .produce' steam-boiler furnaces in which air is introduced into the furnace adjacent to grates from the outside, and I make no claim for such construction.

, 1 upper end, the horizontal flues E communicat ing with said recesses at their inner ends, and their outer ends having communication with the outside atmosphere, said fiues being below the upper end of the bridge-wall, and having sliding stops at their outer ends, whereby the supply of air which it is desired to introduce into the furnace may be regulated, the double arch with apertures (1 leading into the said recesses in the bridge-wall, the central column supporting the inner ends of said arches, which latter extend over the grates a suitable distance, as shown and de scribed. IO

In testimony whereof I afiix my signature in presence of two witnesses.

HOWARD IIARLAN. Witnesses:

J. L. PARKINSON, FVP. RYAN. 

